OUTCOMES OF EXTRACELLULAR VOLUME CHANGE--THE OLDEST OLD

细胞外容量变化的结果——最古老的老人

• 批准号: 6097842
• 负责人: KENNETH L. MINAKER
• 金额: --
• 依托单位: MASSACHUSETTS GENERAL HOSPITAL
• 依托单位国家: 美国
• 财政年份: 1996
• 资助国家: 美国
• 起止时间: 1996-06-01 至 1999-05-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/6097842
• 关键词: aging; aldosterone; arginine vasopressin; atrial natriuretic peptide; blood chemistry; blood pressure; body water; body weight; cardiovascular function; catecholamines; circadian rhythms; dietary sodium; diuresis; echocardiography; exercise; homeostasis; hormone regulation /control mechanism; human old age (65+); human subject; human very old age (85+); norepinephrine; nutrition related tag; posture; renin; salt intake; stress; urinalysis; young adult human (21-34)

The influence of age on the control of extracellular fluid homeostasis has been examined in a systematic series of studies over the past 14 years in the Program Project. This present Project (No. 1) expands observations made during this most recent renewal and initiates a new inquiry - the functional cardiovascular, endocrine and renal outcomes of altered extracellular fluid homeostasis. Compelling preliminary data suggest that healthy elderly individuals have high supine morning as well as a clear diurnal pattern of atrial natriuretic peptide, with an acrophase at 2:00 am. Atrial natriuretic peptide levels are highly correlated with noninvasively determined pulmonary capillary wedge pressures. The impact of these diurnal variations in volume regulation on cardiovascular function during exercise and postural change, as well as on nocturnal diuresis will be measured. Young, old, and old-old sedentary and regularly exercising subjects will participate in these studies. The first hypothesis that there is an age-related diurnal variation in cardiac filling pressures (i.e. ANP levels) associated with a blunted cardiovascular response to exercise, postural stress, and an increased nocturnal diuresis. The second hypothesis is that during chronic extravascular volume expansion (achieved by a high sodium diet), healthy elderly display even higher cardiac filling pressures (i.e. ANP levels) with resultant decreases in cardiovascular performance during exercise and postural stress, and an increased nocturnal diuresis. The third hypothesis is that during chronic extravascular volume contraction (achieved by a low sodium diet), the elderly decrease cardiac filling pressures (i.e. ANP levels) resulting in decreased cardiovascular performance during exercise and postural stress, and a decreased nocturnal diuresis. The fourth hypothesis is that habitually exercising healthy elderly subjects show a profile of ANP values, cardiovascular performance, and nocturnal diuresis pattern more like the young group than the sedentary elderly. We hope that this expanded approach to the relationship between fluid volume and cardiovascular, endocrine and renal functional outcomes in the healthy elderly will enhance understanding of the mechanisms responsible for the morbid disorders of extracellular fluid homeostasis in the elderly.

年龄对控制细胞外液体稳态控制的影响具有 在过去的14年中，在一系列系统的研究中检查了 程序项目。 本项目（第1号）扩展了观察结果 在最近的续约中进行的，并发起了新的询问 - 改变的功能性心血管，内分泌和肾脏结局 细胞外液体稳态。 引人入胜的初步数据表明 健康的老年人有高仰卧早晨，也很清楚 心房纳特里肽的昼夜模式，在2:00时有杂音 是。 心房亚钠肽水平高度相关 肺毛细管楔形压力无创。 影响 这些在心血管功能的体积调节的昼夜变化中 在锻炼和姿势变化期间以及夜间利尿 可以测量。 年轻，老大，老年久坐，定期锻炼 受试者将参加这些研究。 第一个假设是与年龄相关的昼夜变化 与钝的心脏填充压力（即ANP水平） 心血管对运动，姿势压力和增加的反应 夜间动物。 第二个假设是在慢性期间 血管外容量扩张（通过高钠饮食实现），健康 老年人表现出更高的心脏填充压力（即ANP水平） 导致运动过程中心血管表现的降低和 姿势压力，夜间二氧化硅的增加。 第三个假设 是在慢性血管外容量收缩期间（通过低 钠饮食），老年人降低心脏填充压力（即ANP 水平）导致运动过程中的心血管表现降低 和姿势压力，夜间二列赛减少。 第四 假设是习惯性地行使健康的老年受试者表明 ANP值，心血管表现和夜间Diuresis的概况 模式更像年轻人，而不是久坐的老年人。 我们希望那样 这种扩展的方法是流体体积与 健康的心血管，内分泌和肾功能结果 老年人将增强对负责机制的理解 老年人细胞外液体稳态的病态疾病。